Class ColorSpace

This abstract class is used to serve as a color space tag to identify the
specific color space of a Color object or, via a ColorModel object,
of an Image, a BufferedImage, or a GraphicsDevice. It contains
methods that transform colors in a specific color space to/from sRGB
and to/from a well-defined CIEXYZ color space.

For purposes of the methods in this class, colors are represented as
arrays of color components represented as floats in a normalized range
defined by each ColorSpace. For many ColorSpaces (e.g. sRGB), this
range is 0.0 to 1.0. However, some ColorSpaces have components whose
values have a different range. Methods are provided to inquire per
component minimum and maximum normalized values.

Several variables are defined for purposes of referring to color
space types (e.g. TYPE_RGB, TYPE_XYZ, etc.) and to refer to specific
color spaces (e.g. CS_sRGB and CS_CIEXYZ).
sRGB is a proposed standard RGB color space. For more information,
see
http://www.w3.org/pub/WWW/Graphics/Color/sRGB.html
.

The purpose of the methods to transform to/from the well-defined
CIEXYZ color space is to support conversions between any two color
spaces at a reasonably high degree of accuracy. It is expected that
particular implementations of subclasses of ColorSpace (e.g.
ICC_ColorSpace) will support high performance conversion based on
underlying platform color management systems.

The CS_CIEXYZ space used by the toCIEXYZ/fromCIEXYZ methods can be
described as follows:

isCS_sRGB

toRGB

public abstract float[] toRGB(float[] colorvalue)

Transforms a color value assumed to be in this ColorSpace
into a value in the default CS_sRGB color space.

This method transforms color values using algorithms designed
to produce the best perceptual match between input and output
colors. In order to do colorimetric conversion of color values,
you should use the toCIEXYZ
method of this color space to first convert from the input
color space to the CS_CIEXYZ color space, and then use the
fromCIEXYZ method of the CS_sRGB color space to
convert from CS_CIEXYZ to the output color space.
See toCIEXYZ and
fromCIEXYZ for further information.

Parameters:

colorvalue - a float array with length of at least the number
of components in this ColorSpace

fromRGB

public abstract float[] fromRGB(float[] rgbvalue)

Transforms a color value assumed to be in the default CS_sRGB
color space into this ColorSpace.

This method transforms color values using algorithms designed
to produce the best perceptual match between input and output
colors. In order to do colorimetric conversion of color values,
you should use the toCIEXYZ
method of the CS_sRGB color space to first convert from the input
color space to the CS_CIEXYZ color space, and then use the
fromCIEXYZ method of this color space to
convert from CS_CIEXYZ to the output color space.
See toCIEXYZ and
fromCIEXYZ for further information.

Parameters:

rgbvalue - a float array with length of at least 3

Returns:

a float array with length equal to the number of
components in this ColorSpace

toCIEXYZ

public abstract float[] toCIEXYZ(float[] colorvalue)

Transforms a color value assumed to be in this ColorSpace
into the CS_CIEXYZ conversion color space.

This method transforms color values using relative colorimetry,
as defined by the International Color Consortium standard. This
means that the XYZ values returned by this method are represented
relative to the D50 white point of the CS_CIEXYZ color space.
This representation is useful in a two-step color conversion
process in which colors are transformed from an input color
space to CS_CIEXYZ and then to an output color space. This
representation is not the same as the XYZ values that would
be measured from the given color value by a colorimeter.
A further transformation is necessary to compute the XYZ values
that would be measured using current CIE recommended practices.
See the toCIEXYZ method of
ICC_ColorSpace for further information.

Parameters:

colorvalue - a float array with length of at least the number
of components in this ColorSpace

fromCIEXYZ

public abstract float[] fromCIEXYZ(float[] colorvalue)

Transforms a color value assumed to be in the CS_CIEXYZ conversion
color space into this ColorSpace.

This method transforms color values using relative colorimetry,
as defined by the International Color Consortium standard. This
means that the XYZ argument values taken by this method are represented
relative to the D50 white point of the CS_CIEXYZ color space.
This representation is useful in a two-step color conversion
process in which colors are transformed from an input color
space to CS_CIEXYZ and then to an output color space. The color
values returned by this method are not those that would produce
the XYZ value passed to the method when measured by a colorimeter.
If you have XYZ values corresponding to measurements made using
current CIE recommended practices, they must be converted to D50
relative values before being passed to this method.
See the fromCIEXYZ method of
ICC_ColorSpace for further information.

Parameters:

colorvalue - a float array with length of at least 3

Returns:

a float array with length equal to the number of
components in this ColorSpace

getType

public int getType()

Returns the color space type of this ColorSpace (for example
TYPE_RGB, TYPE_XYZ, ...). The type defines the
number of components of the color space and the interpretation,
e.g. TYPE_RGB identifies a color space with three components - red,
green, and blue. It does not define the particular color
characteristics of the space, e.g. the chromaticities of the
primaries.

getMinValue

public float getMinValue(int component)

Returns the minimum normalized color component value for the
specified component. The default implementation in this abstract
class returns 0.0 for all components. Subclasses should override
this method if necessary.

getMaxValue

public float getMaxValue(int component)

Returns the maximum normalized color component value for the
specified component. The default implementation in this abstract
class returns 1.0 for all components. Subclasses should override
this method if necessary.